The present invention relates to an apparatus for producing and storing heated liquid such as hot water. The present invention is also directed to a method of heating a liquid such as water, and storing the same.
Since liquid such as water has a high thermal capacity, production of large quantities of heated liquid such as water requires a large supply of thermal energy.
Apparatus or installations designed for supply of heated liquids such as hot water, are frequently required to cope with demand for a virtually instantaneous supply of very large quantities of heated liquid such as water, which may be followed by extremely long periods during which the demand for heated liquid is practically non-existent. This is especially true for installations or plants that supply domestic hot water in residential buildings, as well as for various installations that produce heated water for industrial purposes.
Previous solutions that have been proposed in the prior art are essentially of two types.
The first type is directed to an installation that is equipped with a heating body having excess capacity that is capable of instantaneously meeting any demand for hot water. This results in excessive overall costs for such an installation, as well as resulting in low combustion yields when the installation is operated at much below its nominal capacity.
A second type of solution involves an installation or plant using a heating body having a nominal capacity substantially corresponding to the average output per unit time (for example 24 hours) normally required for such an installation. This generator is enclosed in a large reservoir, enabling any demand to be supplied instantaneously, essentially by making use of the stratification of hot and cold layers within the reservoir, the hot layers being at the top and the cold layers being underneath. The disadvantage of this type of installation is that it lacks flexibility, particularly with regard to the design of the heating generator inside a storage reservoir of large capacity, and with regard to installing such an apparatus in position.